• 한국산학기술학회논문지
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• 제16권9호
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• pp.5789-5794
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• 2015

최근 스마트 폰, 모바일 PC 제품의 외관에 필요한 가벼운 금속제품으로 제조를 하기 위하여 알루미늄 압출 공정과 CNC 가공기법을 적용한 생산방식이 널리 사용되고 있다. 하지만, 알루미늄 압출법은 외관 디자인의 제약이 있으며, 특히 CNC 가공 프로세스가 상대적으로 높은 생산 비용 및 낮은 생산성으로 생산단가가 많이 높은 단점이 있다. 본 연구에서, 새로운 처리 방법을 순서 재료비를 대폭 감소시키고, 제조 속도를 향상시키기 위해 판재성형과 부피성형의 두가지 공정을 섞어 새로운 판단조 공정을 개발하였다. 새로운 판단조 공법(hybrid plate forging)이란 우선 일반적인 딥드로잉으로 중간 모양을 만든 후 원하는 벽 부위만 증육을 하는 방법을 의미한다. 이러한 판단조 공법을 활용하여 재료의 낭비와 제조 시간을 최소화하는 것이 가능하게 된다. 본 연구에서는 상용 유한 요소 프로그램 AFDEX-2D를 통해 판단조공정을 설계하였고 최적의 사용 가능한 소재의 두께와 초기 폭을 설계하였다. 최종적으로 실제 노트북 케이스 금형을 제작하여 제안한 방법의 타당성을 검증하였다.

• 한국산학기술학회논문지
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• 제14권1호
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• pp.247-256
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• 2013

본 논문은 방문요양서비스를 이용하고 있는 대상자 중심의 서비스 평가를 바탕으로 중요도와 성과도 분석을 통해 관리전략을 제시하였다. 연구대상은 강원도 S시에 소재한 3개소의 재가장기요양기관에서 서비스를 받고 있는 대상자로 하였으며, 자료 분석은 SPSS 12.0을 이용하여 기초통계, 신뢰도분석, 요인분석을 실시하였다. 분석결과 방문요양서비스 중요도는 총5점 만점에 4.55점으로 나타났고, 성과도는 4.26점으로 나타났다. 집중개선영역은 '신속한 서비스 제공'과 '안심하고 서비스 제공'으로 나타났고, 유형성의 4개 속성, 신뢰 확신성의 4개 속성, 대응 공감성의 1개 속성은 개선고려 영역으로 나타났으며, 신뢰 확신성의 3개 속성, 대응 공감성의 5개 속성은 강점유지영역으로 나타났다. 결론적으로 방문요양서비스 질을 높이기 위해서는 우선적으로 집중개선영역의 성과향상이 필요하며, 서비스 제공자의 지속적인 교육과 훈련을 통한 전문성의 확보와 규칙적인 대상자 중심의 서비스 평가를 통한 관리가 필요할 것으로 사료된다.

• 한국소음진동공학회논문집
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• 제24권11호
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• pp.833-839
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• 2014

The shooting noise caused by shooting training, which has strength and impacts, is becoming a serious damage to the residents around the shooting range and, consequently, the number of civil appeals against the shooting noise is on the constant increase. For this reason, the military examines the effects of the shooting noise at the stage of design in constructing a shooting range and tries to build a soundproof shooting range to minimize civil appeals. However, the lack of research and data concerning propagation and attenuation, both of which characterize the shooting noise from within a soundproof shooting range, even makes it so difficult to design a soundproof shooting range in constructing it. So this study used an acoustic simulation in a soundproof shooting range to identify acoustic and propagation characteristics within the shooting range and, on this basis, predicted the noise level at an exit of the soundproof shooting range. As a result, if the form and specifications of a soundproof shooting range were decided on at the stage of design, it was possible to use a simulation to design a soundproof shooting range with optimized acoustic performance and, on this basis, to predict a sound pressure level at an exit of the soundproof shooting range. On the basis of these data, it is probably possible to determine the degree of the effects of the shooting noise on the villages around a shooting range and the extent of damage to it and to minimize civil appeals against the shooting noise and resolve the issues of compensation and agreement with ease. This study is expected to provide useful data for designing and constructing a similar soundproof shooting range.

• 비교문화연구
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• 제27권
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• pp.497-523
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• 2012

Characteristics of the Listening and Pronunciation of Korean Obstruents of Chinese Learners -Based on the Phonetic Experiments Using Kalvin and Praat- This study aims at investigating the characteristics of confrontation in three ways, lax/ fortis/ aspirated consonants, in Korean obstruents through experimental phonetic analysis for the Chinese Korean language learners. On one hand, as a result of comparing Korean and Chinese obstruent systems, there is no big difference regarding the articulatory location. On the other hand, in regards to the articulatory method there is a difference. In a Korean obstruent system, the confrontation presented in three ways by the strength of aspiration. On the contrary, the Chinese obstruent system showed confrontation in two ways by the existence of aspiration. To examine the difficulty of the learners caused by the above-mentioned reason objectively, this paper studied the relationship between input and output of sound through the experimental phonetic analysis such as Kalvin and Praat. To research the input of sound, the listening ability of the learners was examined by 'Choosing Consonant' among the Menu of Kalvin. As a result of that experiment, many errors were shown. They recognized the fortis as lax in the area of affricates and plosives. In the area of fricatives, they recognized affricatives as fricatives. To investigate the output of sound, the section of aspiration and the section of friction of a plosive, an affricate and a fricative in Praat, were expressed numerically. The learners' VOT of lax and affricate represented that lax was pronounced close to the fortis, and the VOT of fricatives was not shown the section of aspiration and friction clearly, and also the result showed that they pronounced a fricative like affricative-aspirated one. The result shows that the learners' pronunciation is related to the listening ability. The consequence is caused by the characteristics of the difference between Korean obstruents and Chinese ones. If the training pronunciation is conducted based on above result, it would be a better methodology in teaching Korean.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2019년도 학술발표회
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• pp.147-147
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• 2019

The Numerical Weather Prediction (NWP) models determine the future state of the weather by forcing current weather conditions into the atmospheric models. The NWP models approximate mathematically the physical dynamics by nonlinear differential equations; however these approximations include uncertainties. The errors of the NWP estimations can be related to the initial and boundary conditions and model parameterization. Development in the meteorological forecast models did not solve the issues related to the inevitable biases. In spite of the efforts to incorporate all sources of uncertainty into the forecast, and regardless of the methodologies applied to generate the forecast ensembles, they are still subject to errors and systematic biases. The statistical post-processing increases the accuracy of the forecast data by decreasing the errors. Error prediction of the NWP models which is updating the NWP model outputs or model output statistics is one of the ways to improve the model forecast. The regression methods (including linear, polynomial and scaling regression) are applied to the present study to improve the real time forecast skill. Such post-processing consists of two main steps. Firstly, regression is built between forecast and measurement, available during a certain training period, and secondly, the regression is applied to new forecasts. In this study, the WRF real-time forecast data, in comparison with the observed data, had systematic biases; the errors related to the NWP model forecasts were reflected in the underestimation of the meteorological data forecast by the WRF model. The promising results will indicate that the post-processing techniques applied in this study improved the meteorological forecast data provided by WRF model. A comparison between various bias correction methods will show the strength and weakness of the each methods.

• Physical Therapy Rehabilitation Science
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• 제3권2호
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• pp.86-92
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• 2014

Objective: Whole body vibration (WBV) and plyometrics are common training techniques which increase strength, blood flow, and lower body force and power. The effects these techniques have on sedentary population is unknown. It is our aim to assess the effectiveness of WBV and plyometrics on sedentary population. Design: Experimental study. Methods: Twenty-seven sedentary subjects were assigned to either the control group, jumping only group, or jumping with vibration group. Jump height (myotest or vertec), velocity, force, blood lactates, and rating of perceived exertion (RPE). Subjects were measured on the initial, seventh, and eighteenth visits. Control group attended measurements only. Jumping only and jumping with vibration groups performed jumping from a vibrating platform to a surface 7 1/2 inches higher for 3 bouts of 20 seconds. Each subject in jumping only and jumping with vibration groups attended three times per week for six weeks. Vibration was set at 40 Hz and 2-4 mm of displacement. Results: There was no significant change among groups in force, velocity, vertec height, and myotest height. However there was a significant increase in vertec height from initial to final measure (p<0.05) for jumping with vibration group. RPE was significantly higher between control group and jumping with vibration group after intervention (p<0.05). Conclusions: WBV with vibration increased jump height. Jumping with vibration group experienced increased exertion than for controls. WBV with plyometrics had no effect on force, velocity, blood lactates, or calculated jump height. Further studies controlling for initial measure of blood lactates and using an external focus may be necessary to elicit velocity, force and jump height changes.

• Physical Therapy Rehabilitation Science
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• 제10권3호
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• pp.244-250
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• 2021

Objective: The purpose of this study was to investigate the effect of sprinter pattern bridging exercise using theraband on activation of lower extremity and abdominal muscle and to find out postures that can effectively improve abdominal and lower extremity muscle strength and increase abdominal stability. Methods: This study was designed as a cross-sectional study. The following research was done with applicants attending S university in Seoul to compare the difference in muscle activity between one-leg-Support bridging exercise and sprinter-pattern bridging exercise using theraband. For 48 study participants, we first measured their MVC. Then, we applied one-leg-support bridging exercise and sprinter-pattern bridging exercise at random order. These data were expressed as the percentage of maximal voluntary contraction (%MVC).Electromyography analysis was performed by measuring the external obliques, internal obliques, biceps femoris, and gluteus maximus. Results: There was a statistically significant increment of muscle activity in external and internal oblique muscle(p<0.001)by sprinter-pattern bridging exercise using theraband. On the lower body, statistically significant increment of muscle activity in biceps femoris and gluteus maximus was found(p<0.05). On the other hand, on erector spinae, there was statistically significant decrease in muscle activity(p<0.05). Conclusions: Efficient treatment is expected when sprinter-pattern bridging exercise using theraband is applied clinically.For patients with chronic knee and ankle pain who have difficulty bearing weight, including low back pain and internal rotation of the femur, starting with a low weight bearing, we think it will be helpful in planning systematic training aimed at progressively strengthening the lower extremities.

• International Journal of Advanced Culture Technology
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• 제6권4호
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• pp.152-157
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• 2018

In the late 19th century and early 20th century, Among those of the Northeast Asia three countries, school physical education and military-style gymnastics of Chosun can be regarded as having been the most nationalistic. The adoption of modern physical education in public schools was from the proclamation of 'the Order on Building the Country through Education by King Gojong in February 1895. This paper intends to examine the process of adopting military-style gymnastics education which played the central role in school physical education in the late Chosun period. But, unlike the common guess that military-style gymnastics in public schools in late Chosun would have been full of patriotism and nationalism, the textbooks and teaching contents of Chosun Military Officers' School were very similar to those of Japan, which is an unexpected fact. Therefore, Chosun decided to accept the Japanese-type military-style gymnastics and military training to improve physical strength of youngsters and military power. The fact that, with the advent of modern education, physical education was emphasized above all else has a very important meaning to the history of Korean physical education. Physical activity education emerged as a major education course which had been unthinkable in previous ages. The second characteristics is that the process of adopting military-style gymnastics and its contents were influenced by Japan Third, even if military-style gymnastics was imported from Japan as part of school physical education course in late Chosun period, its aim was to train military man powers for the independence movement against Japan, rather than to develop harmonious body.

• 대한물리치료과학회지
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• 제25권3호
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• pp.17-24
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• 2018

Purpose: The purpose of this study was to investigate the effect of whole body vibration combined breathing resistance on lung capacity and respiratory muscle and to suggest a mediation method for improvement of respiratory function and lung function in the future. Methods: This study was a preliminary study design of two groups of 54 healthy young adults who were randomly assigned to an experimental group (n=27) with core exercise combined with respiratory resistance and whole body vibration and a control group with respiratory resistance and core exercise (n=27). All interventions consisted of 6 core exercises every 40 seconds and rest for 20 seconds. To compare the effects of intervention, we measured spirometry and respiratory muscle strength. Results: Both the experimental group and the control group showed a significant increase in Forced vital capacity (FVC) and Maximum voluntary ventilation (MVV) (p<.05). However, FEV1 and FEV1% were significantly increase only in the experimental group (p<.05). FVC, FEV1%, Maximum Inspiratory Pressure (MIP), Maximum Expiratory Pressure (MEP) showed more significant increase in the experimental group than the control group. Conclusion: These findings indicate that whole-body vibration combined breathing resistance is an effective intervention for people, with FVC, FEV1%, MIP, MEP increase.

• 한국응용과학기술학회지
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• 제36권1호
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• pp.189-199
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• 2019

이 연구의 목적은 복합운동이 노인여성의 낙상관련 지표 및 마이오카인에 미치는 효과를 보는데 있다. 근감소증은 근력의 손실로 인해 발생하고, 기능적 상태의 감소, 활동력의 저하에 따른 낙상의 위험성이 높아지고 끝내 사망의 위험성이 높아지게 된다. 유산소운동은 대근을 이용한 리듬과 반복적인 동작으로 특징 지워지고 주로 유산소성 대사를 통한 산소를 에너지 이용으로 심폐체력, 체성분 및 심장과 호흡계 건강에 기여한다. 한편 저항운동은 근육에 스트레스를 가해 노인들의 근력관련 체력과 기능적 수행 개선에 기여한다. 근기능 및 심폐지구력 향상을 꾀하는 복합운동은 노년들의 효과적인 건강증진에 기여하는 것으로 나타내고 있다. 근육에서 분비되는 마이오카인은 운동에 중요한 요인으로 간주되고 있는데 지방세포 감소, 골격, 근육 및 인체 전반에 걸쳐 유익한 효과를 보인다.